In this case I’m taking the word “greatest” more as “biggest/most impactful” and not necessarily “most good”

Yeah that’s what I meant, I agree with the topic of “it might be what started workers exploitation”, but what I’m talking about is “it’s an invention/discovery that was so powerful to shift the natural behaviour of a species”. We’re not even talking about antropology now, it’s an etological impact and there haven’t been many others in our history